Combinibg Coded Block Patterns and Co-located Macroblock Correlation for H.264 Fast Mode Decision

• Main Authors: Kuo-Hsin Wang, 王國信
• Other Authors: 楊士萱
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/jrap45

碩士 === 國立臺北科技大學 === 資訊工程系研究所 === 97 === The H.264 video coding standard substantially improves compression performance and visual quality by using more flexible coding options, notably the inter-mode selection and multiple reference frames. This thesis aims at reducing the H.264 encoding complexity for fulfilling the real-time requirement of conversational video services. The proposed method integrates the coded block pattern (CBP) and information of the co-located macroblock to avoid RDcost evaluations of all possible modes. The CBP is a syntax element in the H.264 macroblock layer, which specifies which of the six 8x8 blocks after motion estimation requires residual coding. The co-located macroblock in the reference frame is situated at the same position as the current macroblock. The CBP value and the coding mode of the co-located macroblock can be used to predict the most possible inter-mode of current macroblocks. We extensively evaluate accuracy and efficiency for each of the simplifying criteria, and incorporate them into a fast-mode-decision algorithm. Experimental results confirm that the proposed fast mode decision algorithm can reduce the encoding time by approximately 75% at medium-to-low bit rates without sacrificing the visual quality.